What is the pythagorean theorem and how do i use it?

I actually just learned this in 8th grade and it was so easy its crazy but its honestly simple it helps you solve the triangles and things and the equation is a squared + b squared = c squared and the a and b you would plug in the sides of the triangle or whatever shape your working with and square those numbers then find c by adding the two and then you square the c at the end and that will be your answer.

I’m having a hard time understanding your question